was successfully added to your cart.



Transmission & Drivetrain

An Overview of The GM Turbo 350 Performance Transmission

Turbo 350 Transmission - Gearstar

Many experts consider the Turbo 350 Transmission perfect for light trucks, rally races, and entry-level sports vehicles. What makes this transmission unique is its tough parts and high performance, which give it the capacity to tackle several use cases.

Gearstar innovatively produces level two, three, and four automatic transmissions heavily backed by a full warranty.


The Turbo 350 Transmission – better known as the Hydramatic 350 – is a 3-speed automatic that debuted as a joint Chevrolet/Buick project in 1969. The primary objective of this project was to replace the Super Turbine 300 2-speed Powerglide automatic.

The project also spawned several transmissions, including the 250, 250c, 350c, and 375b GM transmissions.

Identifying the GM Turbo 350 Performance Transmission

When General Motors introduced the Turbo 350 to the world, the latter was encased in a one-piece aluminum alloy housing unit. This unit measures 21.75 inches long and is comparatively light as it weighs up to 120 lbs.

It comes with a custom-made oil pan that fits in perfectly, as well as a chamfer at the rear passenger side. You can find the modulator by looking at the back of the case.

General Motors installed a lock-up torque converter in vehicles made from 1979 to 1984. This converter utilized electronic converters to make the vehicle and transmission much more fuel-efficient, especially when moving at highway speeds.

Drivers can identify the lock-up converter via an electrical plug on the driver’s side of the transmission. A plug on the left side shows you have a 350-C on your hands. Adding aftermarket conversions to these transmissions can still be worthwhile today, with up to 10 percent more fuel efficiency.

Turbo 350 Performance Transmission: Specs

General Motors introduced the Turbo 350 Transmission to conveniently replace the highly revered Powerglide 2-speed automatics in the 1960s. The following are the gear ratios the Turbo 350 features:

  • First gear: 2.52 to 1
  • Second gear: 1.52 to 1
  • Third gear: direct drive, i.e., 1.0 to 1
  • Reverse: 2.07 to 1

The Turbo 350 has no overdrive gear available.

On the contrary, the Powerglide came with the following gear ratios:

  • First: 1.82-to-1 /1.76-to-1
  • Second: 1.00-to-1

The Turbo 350 powers classic American muscle and its venerable specifications are as follows:

  • Level 2, Level 3, and Level 4 performance
  • The ability to take on as much as 700 horsepower
  • The capacity to control as much as 400 lb-ft. of torque

The power of your classic American muscle determines the horsepower you need, as much better engines will require a minimum Level 3 transmission. Due to considerable modifications, the particular transmission that handles your build with strong parts and high-quality build is always available.

The Turbo 350 shares several components – including the torque converter – with the Buick Super Turbine Powerglide and the Turbo 400. This transmission remained in production for up to 15 years until it was fully replaced in 1984 by the 700R4.

In 1980, the lockup torque converter was added but pulled four years later because of its downshifting and inconsistent acceleration.

The Turbo 350 Transmission: Construction and Size

The Turbo 350 Transmission is a single-piece transmission with a bell housing perfectly integrated into the transmission body. The entire transmission casing is made of cast aluminum.

The Turbo 350 is renowned for its short length, making it one of the lightest transmissions ever made. It takes up to 4 quarts in a pan and may require a little extra based on the torque converter in action.

When combined with a 9.5-inch converter, the overall requirement is about 10 quarts.

The additional gear the Turbo 350 came with made a no-brainer choice compared to its predecessor. This is why it is widely employed in nearly all rear-wheel vehicles – from General Motors – at the time.

Its strength, compactness, and versatility have made many vintage or classic car owners retain the transmission’s use to this day. Most vintage cars sold today also come with this powerful transmission, with minor alterations.

Turbo 350 Transmission: Benefits

The Turbo 350 empowers every driver to take their hobbies to a higher level. Only a few drivers are privileged to start their journey with the best available vehicle or the most horsepower.

If you are very new to the sport or looking to power your daily driver conveniently, the Turbo 350 is an excellent option.

The most profound benefit that the Turbo 350 brought to the table was its extra gear, one up from its predecessor. This transmission is also compact, strong, and versatile.

The Turbo 350 only had one notable weakness: the wobbling of the direct clutch drum.

Most Common Uses of the Turbo 350 Transmission

The Turbo 350 Transmission found excellent use in Pontiac Firebirds, GMC trucks, Chevrolet Camaros, Monte Carlo, and the Caprice. This transmission remarkably matches GM automobiles with small-block V-8s as well as the small Iron Duke 4-cylinder models, the block-block 396 V-8s, and V-6s.

The BOP (Buick, Oldsmobile, and Pontiac) is an offshoot version of the standard Turbo 350 that works with the Pontiac V8. You can easily differentiate one from the other by looking at the block flange. The BOP version comes with a valley, while the Chevrolet model showcases a peak.

General Motors also created several derivatives of the Turbo 350, including lock-up torque converter models with the smaller TH375, TH 250, and TH20.


The Turbo 350 Transmission works remarkably well with many modestly powered vehicles. It was versatile in the 1960s since it had no fixed center support and could be used in several experimental vehicles.

Even though the Turbo 350  is no longer in production, it is still employed by several classic vehicle builds. It comes with extra gear, which gives it a significant advantage over its predecessor.

The Turbo 350 Transmission is also versatile, strong, and compact. During its time, its overall strength and versatility made it popularly used in many rear-wheel automobiles from General Motors. It is still in use in several vintage or classic vehicles today.

History of the 4L60E and How It Stacks Up Against the 4L80E

4L60E - Gearstar

The 4L60E is one of General Motors’ most versatile and durable 4-speed transmissions. So how does it stack up to it’s counterparts?

The 4L60E – whose components bear remarkable similarities with 4L65E automatics – is a series of automatics transmissions produced by General Motors. It is primarily designed for longitudinal engine configurations and includes four forward gears and one reverse gear.

Brief History of the 4L60E

The 4L60E is one of General Motors’ most versatile and durable 4-speed transmissions. It was formerly known as Turbo-Hydramatic 700R4 and is currently the electronic version that is popular today: 4L60E. General Motors manufactures the remarkable 4L60E in Romulus, Michigan, and Toledo, Ohio.

In 1982, General Motors initially conceptualized the 4L60 and 4L60E as the 4-speed overdrive automatic transmission known as TH700R4. At the time, the multinational corporation was urgently looking for several fuel-efficient methods to power its vehicles. This was right after the unfortunate ’70s fuel shortages that resulted in the massive influx of Japanese to North America. 

A recession in the early ’80s and rapidly-increasing fuel costs right at the pump had a massive and disastrous impact on auto sales. Since the -speed TH700R4 was much more efficient, it quickly replaced its three-speed counterpart, TH350. 

At the time, the Turbo 700 had a lower 3.06-to-1 final gear ratio – along with a 30 percent overdrive – that provided quick acceleration from a dead stop. However, the early versions of the TH700R4 went through growing pains as General Motors continued to kick out bugs for improvement. The multinational automaker was recklessly determined to make a resounding success of the four-speed TH700R4. 

The Arrival of the 4L60 and 4L60E

In 1990, the automaker conveniently renamed the TH700R4 as the 4L60 to fully manifest its primary purpose as a 4-speed automatic with a longitudinally-placed matching engine and an overall vehicle weight rating of approximately 6,000 lbs. Note that the ‘4’ in both names represents ‘four gears’ while the ‘L’ stands for ‘oriented longitudinally.’

However, General Motors did not make any mechanical changes whatsoever to the TH700R4. And by 1997, this electronically-controlled shift version became much more available in 2- and 4-wheel drive trucks as well as rear-wheel-drive cars. Even the 6th generation Chevrolet Corvette was also fitted out with the 4L60E transmission. 

The 4L60E used electronic actuators and solenoids to control the valve body, clutches, and bands to shift gears. General Motors’ Vehicle Speed Sensor and a vehicle powertrain computer always determined precisely when gear shifting was optimum.

The 4L60E has different gear ratios:

  • 3.05-to-1 for first
  • 1.625-to-1 for second
  • 1.00-to-1 for third
  • 0.696-to-1 for fourth 
  • The 2.29-to-1 ratio for the reverse

How 4L60E Stacks Up Against the 4L80E

The automaker built the 4L60E as well as 4L80E, both of which are automotive transmissions. As stated earlier in this post, the 4L60E is the standard transmission used in many rear-wheel automobiles manufactured after 1993.

However, the 4L80E is generally limited to big block and diesel vehicles. It must be mentioned that these two automotive transmissions differ significantly in performance, origin, appearance, gear ratios, price, weight, size, etc. And, of course, the 4L80E automotive transmission is much more powerful than its counterpart, the 4L60E.

The 4L60E and 4L80E performance transmissions have similarities, such as being manufactured by General Motors and have a 4-speed automatic overdrive, respectively. This is where the considerable similarities between the two performance transmission models end.

Let’s take a look at the factors that stack 4L60E up against the 4L80E:

The Origin

Although the 4L60E and 4L80E share similar model numbers, there are marked differences between the two automotive transmissions. They are so different from each other, even right down to precisely how they are manufactured respectively. 

The 4L80E is an electronic overdrive successor of the Turbo 400 and is an earlier transmission model greatly favored by hot rod enthusiasts and drag racers.

On the other hand, the 4L60E automotive transmission is electronic transmission-based right off the 700-R4. This was fundamentally the standard transmission for GMC and Chevrolet vehicles right from 1982. 

The Appearance

The 4L80E automotive transmission is much larger than its counterpart, the 4L60E. It has an oval-shaped pan, while the 4L60E automotive transmission comes with a rectangular pan.

Moreover, the 4L80E transmission also requires many bolts – more than is necessary for the 4L60E automotive transmission – to secure it to the engine. This corresponds with more outstanding durability and a bigger size. 

There is also a gasket of up to 17 bolts on the 4L80E transmission unit, while the 4L60E unit has only 16 bolts.

The ’80’ in 4L80E implies that the transmission unit can support up to 8,000lbs. Of GVWR while the ’60’ in 4L60E means that this automotive transmission unit can handle up to 6,000 GVW. The ‘E’ in both models stands for ‘electronically’ controlled transmissions.

The Power

The 4L80E is undoubtedly the more powerful of the two automotive transmissions. High-speed automobiles for racing or big trucks used for towing vehicles or cargo generally require a 4L80E automotive transmission instead of the 4L60E. 

This is because the engine’s power is much more likely to break less powerful and smaller transmissions. But then, the 4L60E automotive transmission is powerful enough to work with the engines of most stock automobiles. 

The Size and Weight

The size and weight of both automotive transmission units are vastly different. The 4L80E is heavier – up to 236 pounds – and larger – with a length of 26.4 inches – than its counterpart, the 4L60E. 

However, the 4L60E weighs a mere 150 pounds – without any fluid – and has a length of 23.5 inches.

The amount of fluid these automotive transmission units will support depends primarily on the torque converter utilized in the transmission.

The Price

The 4L80E automotive transmission is much more expensive than its counterpart. The 4L80E is more powerful, larger, specifically manufactured, and designed for engines with significant horsepower. 

This 4L80E automotive transmission is a much better investment for high-speed vehicles and heavy-duty trucks with big engines. The 4L60E is much more susceptible to breaking, especially when installed on high horsepower engines.


The differences in the performances of the 4L60E and 4L80E automotive transmission units are numerous. And they show that the latter – i.e., the 4L80E transmission unit – is the better of the two.

However, it will cost you much more money to acquire the 4L80E transmission unit and is also relatively easier to find.

Therefore, if your vehicle demands applications that wear down the transmission, you may have to go for the 4L80E unit. But suppose you love driving at high speeds. In that case, the 4L60E automotive transmission unit is the best option since you will use a stock transmission that can significantly handle your vehicle’s engine power.


Swapping a TH200 4R Into an Early Muscle Car for Easy Overdrive

Swapping a TH200 4R Into an Early Muscle Car - Gearstar Performance Transmissions

Would you like to know how to swap a TH200 4R transmission into early muscle cars for easy overdrive? If that is a yes, let us show you how to go through the whole process. First off, it is worth noting that the TH200 4R transmission is worth the time and effort you will put into swapping it into that ride of your choice.

The reason lies in the ruggedness of this transmission, which can be compared to the 700R4. In line with that, a few modifications to the TH200 4R will see this transmission nicely fitted into almost all Chevy chassis. You will also be spending less to get this transmission since it is the least expensive overdrive automatic.

Advantages of Using a TH200 4R Transmission

There are several advantages of using the TH200 transmission to swap into a muscle car:

1. As Strong as the TH700-R4

The TH200 4R shows the same torque capacity and durability evident on the TH700-R4. And the TH700-R4 is a performance automatic overdrive that has earned a lot of attention.

2. Gear Ratio

The TH200 4R has a better first-gear ratio. Specifically, this transmission uses a 2.74:1 First-gear ratio, and in comparison to the TH350’s ratio, it is more profound. Nonetheless, it is less deep than the TH700-R4’s 3.06:1 ratio. Also, there is a less severe RPM drop of the TH200 4R’s engine between first and second gear, and as such, the car accelerates after the gear change. It may also interest you to know that overdrive ratios between the TH200 4R and the 700-R4 are almost similar. These ratios are 0.67 and 0.70, respectively.

3. Compatibility

The TH200 4R is also a suitable replacement for powerglide/TH350 transmissions. It has the same basic overall length as the powerglide or Turbo 350 automatics. In line with that, it uses a similar 27-spline slip-yoke as a powerglide or a TH350 transmission. You will also find standard flexplates on this transmission. Accordingly, here is how to swap the TH200 4R transmission into early muscle cars.

Swapping a TH200 4R Into an Early Muscle Car - Gearstar Performance Transmissions

How to Swap TH200 4R Transmission into Early Muscle Cars

The TH200 4R can easily be identified from other transmissions, including the TH350 and TH400, thanks to its unique pan design. And when it comes to swapping this unit into muscle cars, you need to choose a well-used TH200 4R. With that in mind, here is what you need to begin:

1. Universal TV Cable and Bracket

You will need to purchase a throttle valve (TV) cable and two different cable brackets. The cable brackets will be used for the Holley or Carter/Quadrajet Carburetor. It is essential to get these dedicated brackets to ensure good positioning of the TV cable to the primary throttle shaft.

2. Throttle Valve (TV) Cable

We’ll like to emphasize the throttle valve (TV) cable, on which the TH200 4R relies on. This cable serves as a replacement for the vacuum modulator valve and the kick-down linkage. It is essential to install and connect this cable properly. The connection between the TV cable and the transmission is made on the passenger side using a small hook. On the other hand, you can run the Turbo 350 or a powerglide without the kick-down cable, unlike the overdrive transmissions like the TH200 4R and 700R4 that need the TV cable adequately connected and adjusted. The TV cable helps to baseload on throttle position, which makes it essential. Not adjusting the cable properly, the clutches may get damaged within a short time due to high load with low trans pressure.

3. TV Cable Adjustment

You may want to carry out a TV cable adjustment to ensure that the cable is tight with the carburetor at wide-open throttle (WOT). What this adjustment does is to create maximum transmission-line pressure at WOT. Nonetheless, harsh part-throttle upshifts may be created if the cable is too tight. As such, you can loosen the cable to reduce inline pressure to soften the harshness slightly. A dimension you should consider is the distance from the throttle shaft to the TV cable connection.

4. Torque Converter

Swapping to a TH200 4R requires that you select the right torque converter. You can opt for a modified converter that is smaller with a higher-stall and lockup-style converter. The latter differs from a stock torque converter that is heavy. There are torque converters that support 2,600-4,000 stalls, and these can lock up under cruise conditions. They are also ideal for hot street cars with a big cam and deep gears. It is entirely possible to interchange TH200 4R converters with some early 700-R4 transmissions. In contrast, you cannot interchange Turbo 350, 400, or powerglide converters with the TH200 4R. On the other hand, it is easy to tell apart lockup converters using the converter’s flat flexplate side.

5. Wiring Kit

There is a universal lockup wiring kit you can use to retrofit TH200 4R and 700R4 automatics. The aim of doing this is to engage the lockup converter in fourth gear and, at the same time, disengage the lockup under the acceleration of downshifting. Over and above that, the kit offers a manual override option, which is beneficial if you opt for a lockup torque converter.

Swapping a TH200 4R Into an Early Muscle Car - Gearstar Performance Transmissions

The Bottom Line

The steps above will get you started with swapping a TH200 4R transmission into early muscle cars. You will be working with a durable and robust transmission that comes with other advantages. It will withstand the impact on the road while you race; hence, it is worth using this transmission in the first place. Now try these installation tips above to see how well they work for you.

Ford 4R70W Transmission History and Evolution

Ford 4R70W History and Evolution - Gearstar Performance Transmissions

The Ford 4R70W transmission history and evolution has been an interesting one. It began with more fuel-efficient cars, given the high gasoline cost to run these vehicles. There was also a low supply of fuel, which made it expensive to drive heavy automobiles, large-displacement carbureted V-8s, 2- and 3-speed straight-drive automatics, and other cars.

As such, car manufacturers, including Ford, had to include components that will make cars run longer but with less fuel. One such modification led to the Ford 4R70W transmission launch, an upgrade to the Ford AOD transmission. Here is all you need to know about the 4R70W’s history, evolution, and how it differs from the AOD transmission.

History of the Ford 4R70W Transmission

The 4R70W denotes:

    • Four-speed
    • Rear-wheel drive (RWD)
    • 700ft-lbs (input torque in ft-lbs x 10)
    • Wide-ratio

The history of the 4R70W transmission can be traced to Ford’s automatic overdrive (AOD). AOD was launched in 1980, and it was the first domestic automatic overdrive transmission targeted at providing fuel-efficiency. This transmission featured hydro-mechanicals and direct overdrive lockup to mitigate wasteful slippage. The AOD also featured Ravigneaux geartrain components that made it rugged. However, there was still a need for improvement since the AOD had durability problems, especially in its overdrive unit.

Accordingly, the AOD Electronic Control (AODE)/4R70W was launched in 1991 to tackle these problems. The AODE was also meant to provide a more cohesive functioning of the engine and transmission. It is worth noting that the name AODE was maintained between 1991 to 1992 before introducing the 4R70W (which is also an AODE) in 1993. The 4R70W was fitted behind the 4.6L dual overhead cam (DOHC) V-8 in the new Lincoln Mark VIII and some F-Series trucks launched in the same year.

Functions of the Ford 4R70W Transmission

The 4R70W is also an AODE transmission; as such, its features are like an AODE. Some of these features help to identify the transmission from an AOD, and they include:

1. Gear Ratios

    • First: 2.84.1
    • Second: 1.55:1
    • Third: 1.00:1
    • Overdrive: 0.70:1
    • Reverse: 2.23:1

The 4R70W differs from the AODE in terms of gear ratios. This transmission has lower gear ratios in first and second gears, which brings about improved acceleration. The 4R70W planetary gearset, with its improved first-gear ratio, also offers better acceleration. In line with that, the 4R70W gearset can be swapped into an AOD if you are out to get better 2.84:1 to 1.55:1 1-2 upshift and holeshot.

2. Locking Torque Converter

4R70W uses a locking torque converter, which differs from the split-torque overdrive unit lockup feature evident on the AOD. According to Ford, a locking torque converter was to build a more cohesive engine and driveline package. A throttle tip-in while you are in overdrive, causes the converter clutch to disengage, and the latter leads to improved acceleration and torque multiplication.

3. New-and-Improved Valve Body

You will find a new-and-improved valve body in the 4R70W transmission. There are also two computer-controlled solenoid packages, and these have two shift solenoids and a converter clutch solenoid. Ford claims that this valve body is thicker, which offers more strength and durability. These valves are also made of aluminum, unlike steel in AOD, to offer decrease weight and improved sealing. Other components of the 4R70W are:

4. Front Pump

The 4R70W has a front pump made of aluminum, and it also has a steel rotor to provide better flow at idle and increased lubrication and pressure.

5. Speedometer Drive

Given that the 4R70W is an AOD-based transmission, it also features a speedometer drive.

6. Backup Light/Neutral Safety Switch

The 4R70W transmission has a backup light/neutral safety switch. The output shaft speed sensor is located above the switch, and it functions alongside the PCM to enable the engine and transmission function cohesively.

7. Output-Shaft Speed Sensor and Plug

The 4R70W has its output-shaft speed sensor and plug stationed on the driver’s side. On the other hand, the multiplex plug serves as a backup light/neutral safety switch on the transmission driver’s side.

8. 4R70W Multiplex Plug Connection

The 4R70W has a multiplex plug connection, which enables controlled AOD to operate seamlessly with engine operation. A TV cable is not used to move out of adjustment but electronics to offer precision function.

Evolution of the Ford 4R70W Transmission

Better transmissions are being made from older ones, which does not come as a surprise that the 4R70W has evolved. In 2003, the 4R75W and 4R75E were launched as better variants of the 4R70W. These modified versions have better computer control, given that they use input and output shaft sensors. What is more, better improvements can be attributed to shifting power via the valve body. These enhanced variants also have a more durable overdrive drum, improved front pump, and torque converter.

Other improvements made on the 4R75W and 4R75E include:

    • Improved input shaft sensor.
    • Gearset durability and torque capacity improvement.
    • Refined vehicle speed sensor to fine-tune performance while driving.
    • Twenty-four tabs on the 4R75’s ring gear to offer for more precise shift control.
    • More programming in the powertrain control module (PCM) to allow use in drive-by-wire vehicles.
    • The 4R75W and 4R75E feature two shaft sensors for input and output shafts. However, the 4R75-series transmission comes with a different main case to support both sensors.

The Bottom Line

The Ford 4R70W history and evolution show how far it has come and the updates it underwent to be better than its predecessor. It uses fuel efficiently and makes room for other improvements, which makes your driving experience more enjoyable. Although this is an old transmission, it is still a formidable competitor to newer transmissions from Ford.

Top Signs It’s Time for a Transmission Rebuild

Top Signs It's Time for a Transmission Rebuild - Gearstar Performance Transmissions

 Keeping a close eye on the top signs it’s time for a transmission rebuild will ensure the proper functioning of your transmission for a long time. It will also save you money in the long run due to the importance of this piece of machinery in your car. In this case, the transmission is responsible for moving power from the engine to the wheels through a series of gears.

The transmission is also a highly intricate unit with several moving parts, which requires scheduled maintenance to keep these parts running at their best. Accordingly, whether your car has a manual, automatic, or semi-automatic transmission, here are top signs it’s time for a transmission rebuild.

Warning Signs of Transmission Trouble

So, when does a transmission need to be rebuilt? Let us show you some of the signs to be on the watch for. And if you spot any of these signs of transmission failure, contact your local repair shop to get the unit fixed immediately.

Grinding Gears

Got trouble shifting and even hearing a sound like two metals grinding on each other? Then it is a top sign of transmission issue. This issue may stem from low or no transmission fluid in the gears. Another possible cause of grinding gears is if the gear teeth have worn out. That being said, the latter issue can be resolved by rebuilding the transmission to revive it again.

Leaking Transmission Fluid

If your transmission fluid is leaking, then it is a major cause for concern. But how can you tell when this fluid is leaking? You need to keep a close eye for a red fluid discharging from the transmission. Continuous leaking of the fluid will lead to low transmission fluid levels, which could hinder the operation of your automatic transmission and impact negatively on your car.

Therefore, get this issue checked as soon as possible and keep in mind that a full transmission rebuild may be needed to resolve it. Nonetheless, you can easily replace the seal that is leaking before refilling with fluid if the leak is minimal. The reverse is the case if the leak has occurred for several miles and thus, a full rebuild is needed.

Slower Shifting

If your automatic transmission lags while trying to shift and does not respond immediately, you may need to take a closer look at it. This delayed shifting may be caused by low transmission fluid. Therefore, add more fluid to the reservoir and take the extra step to inform a mechanic of the issue. On the other hand, if your transmission will not even shift into gear or reverse, a rebuild may be needed. The problem stems from worn-out gear teeth that prevent the transmission from engaging.

Burning Transmission Odor

Detecting a burning odor that can be likened to that of burning plastic is a sign of a faulty transmission. Here, transmission fluid lubricates the moving parts within the mechanism, and this smell could indicate that the transmission fluid is overheating. A problem of this nature needs to be fixed immediately to prevent the unit from failing completely. The odd smell may also indicate that your car’s clutch needs to be repaired or adjusted.

Strange Sounds

It can save you money in the long run if you do not ignore any weird sounds that your transmission is producing. These weird sounds may be produced when the car is in neutral or while shifting or driving. Some sounds you should keep an open ear to include whining or grinding and either of these indicate that there may be problems with your transmission. Accordingly, get a repair specialist to examine your vehicle and make a proper diagnosis of the issue.

Popping Out of Gear

Your car may tend to pop out of gear every now and then which is a sign of a mechanical problem. This issue can impact on the ride and even pose a risk to the driver. This is because each time the car pops out of gear, it could make it difficult to properly control the vehicle. It also means you could smash into other cars and put its passengers at risk. That being said, call a technician to come to look at your car to get the issue fixed.

Is a Transmission Rebuild Worth It?

Many have wondered. “Is it worth getting a transmission rebuild?” The answer is yes especially if it has been recommended by your car technician or the repair shop you are using. And most importantly, if you experience any of the signs listed above, then it will be worth giving your transmission a rebuild to get it running smoothly again.

What to expect after a transmission rebuild makes the whole process worth it. It gets even better when you do not skip the scheduled transmission maintenance for your ride and have a professional in the field handle its rebuild. The technician will get the transmission repaired before it gets worse.

The Bottom Line

The top signs it is time for a transmission rebuild should always be at your fingertips to ensure your transmission is always in good condition. These signs may vary depending on the cause, hence, do not ignore them each time you spot one or the other.

The goal is to enable the transmission to carry out its basic function with ease and reduce the potential for your vehicle to break down unexpectedly. Therefore, it is up to you to ensure your sleek ride is always in good shape to hit the road.

How to Choose the Right Performance Transmission Fluid

How to Choose the Right Performance Transmission Fluid - Gearstar Performance Transmissions

There are several automatic transmission fluids on the market today, which could make it a bit challenging to ascertain the best fluid for your car. However, that should no longer be the case given that we’ve outlined easy ways on how to choose the right performance transmission fluid for your car. Prior to this time, the decision of choosing between fluids was easy since cars basically relied on two-fluid types.

These fluids were Type F and GM’s DEXRON. Today, the need for improved fuel mileage has led OE manufacturers to create their own fluid, which is why you will find different automatic transmissions fluids. There are Chrysler‘s +3 and +4 fluids, seven fluids from Ford, and DEXRON versions III and VI fluids. So, how can you choose the right performance transmission fluid for your car? Read on to find out!

Selecting the Right Automatic Transmission

Some reasons why you need the right automatic transmission includes:

1. Requirements

Although there is a vast array of car lubricants from different manufacturers, each maker has designed its specific fluid to meet a narrow set of requirements. The increase in the number of gears and various automatic transmission types has also increased the types of fluids on the market.

2. Backwards Compatibility

There are often claims that the latest ATFs are backwards compatible, but the latter is not always the case. An instance is the GM 4L60E automatic transmission in the 2000 Camaro or Corvette. Here, the DEXRON-VI is often recommended as the best fluid for this transmission since it has a lower viscosity fluid and a more stable viscosity at a higher temperature.

On paper, it would mean that the DEXRON-VI is also backward compatible with older transmissions like the TH350 and TH400 transmissions. But this is not the case given that DEXRON-VI is best for newer vehicles.

First off, DEXRON-VI was released in 2005, which means older transmissions were filled with DEXRON-III from the factory. While DEXRON-VI will work in these transmissions, recent experiments of DEXRON-VI in cars originally designed to use DEXRON-III showed a slight increase in the converter stall speed.

Choosing the Right Performance Transmission Fluid

To choose the right performance transmission fluid for your car, consider the following:

Type F Transmission Fluid

For transmissions designed after 2000, it is ideal to use the most modern ATF. This is because automatics made in the twenty-first century are designed to use fluids with added friction modifiers additives to soften clutch engagement. And for transmissions designed before 2000, it is better to settle for a more traditional fluid.

A good fluid that is recommended for most older transmissions is Ford Type F fluid. There is the original Ford Type F fluid, and it was formulated with a reduced friction modifier package. This design was intended to create quick clutch engagement and reduce clutch slippage. It is also possible to use the DEXRON-VI in these vehicles even though they are not the best choice, which means you can opt for the DEXRON-III fluid.

Transmission Fluid Additives

There are companies that create different versions of the Type F fluid to aid drag racing. These versions often include a 20 weight and 30 weight version, and both are pure synthetic fluids. A heavy car that has more torque will rely on the 30W while other cars can use the lighter fluid. The lighter fluid can also be used to adjust stall speed significantly higher.

While it may be useful to use these synthetic fluids, it is worth noting that you should not mix fluids that have different additive packages. An instance is the Chrysler +4 fluid that relies on a different additive package compared to DEXRON, and Mercon.

Multi-Vehicle ATF

Several companies have launched multi-compatible fluids to ensure you choose the right one for your car. There are fluids that are a combination of DEXRON and Mercon fluids. However, the factory specs of each fluid vary even though it is close enough for a single ATF to achieve both.

On the other hand, do not settle for fluids that claim to be suited for all vehicles. The reason lies in the fact that a more universal fluid is not ideal for a performance transmission. In line with that, do not use ATFs intended for continuously variable transmissions (CVT) on older automatics.

The same applies to fluids that are labelled as low viscosity (LV) or ultra-low viscosity (ULV). This is because these fluids consist of unique friction modifiers that are meant to meet certain mileage goals. These goals are counter-productive to a performance application.

Synthetic Transmission Fluid

Synthetic transmission fluid refers to the quality of the base oil, which is important for temperature stability. Accordingly, it would be useful to settle for a pure synthetic base stock since it is the best ATF to use for your performance transmission. Synthetic ATF offers superior thermal stability, which is beneficial for performance automatics with high-stall converters that tend to generate a high amount of heat.

The heat can impact on the fluid’s addictive packages negatively and thereby reduce their performance. In contrast, a more stable synthetic ATF will not lose its qualities over an extended time and it can withstand high temperature to still protect the transmission from damage.

The Bottom Line

These are the simple steps on how to choose the right performance transmission fluid for your car. Following this guide will ensure you choose a fluid that can is right for your performance transmission. Your automatic transmission will perform to the best of its ability and stand the test of time with the right lubricant in it.

On the other hand, older transmissions launched before 2000 can also benefit from the use of fluids originally made for them. The bottom line is the right fluid will offer the best performance during drag racing and save you frequent trips to the repair shop.

GM Transmission Recommendations for High Performance

Turbo 350 Transmission - Gearstar

Here is our guide to the GM transmission recommendations for high performance to ensure you get the best automatic transmission for drag racing. You will be getting an engine that is durable, lightweight, and efficient. First off, GM overdrive automatics are quite popular on the street, whereas powerglide and TH400 are notable on the staging lanes of dragstrips.

Race cars such as street/strip machines, Fords, Mopars, Chevys, Top Alcohol dragsters, or 3,000hp Outlaw 10.5 beasts rely on drag racing transmissions from GM or bust. Accordingly, we have outlined some recommendations to look forward to and factors to consider such as reaction time, OE durability, and powerglide perks.

GM Transmission Recommendations for High Performance

Here is a more detailed outline of our top GM transmission recommendations for high performance. They include:

Powerglide vs TH400

The powerglide and TH400 are often used as the standard for durability in competitive drag racing. There are applications where the powerglide is better used, and certain cases where the TH400 is more suited. But what application are each of these suited?

The powerglide is a better option when dealing with cars that do not weigh more than 3,200 pounds. These vehicles also launch violently and may be traction limited. And when dealing with race cars, the TH400 is ideal for cars with large tires and taller rear end gearing.

TH350 Alternative

There is the TH350, which is a good compromise when compared to the TH400 and powerglide. The TH350 has something similar to the TH400, which is its three forward gears with less rotating mass. On the other hand, the TH350 may need expensive components to be on par with the powerglide or TH400 to handle all the racing you may need without intermediate sprag or snapping the input shaft.

The stock versions of the powerglide and TH400’s planetaries, drums, and shafts are more rugged than the TH350. That is not to say that the TH350 cannot be upgraded to be on the same level with entry-level powerglide and TH400s that have been enhanced with premium frictions and steels. In this case, the upgrade can be made possible with a sprag-type intermediate overrun clutch, a late 700R4 low roller clutch center support, a 300M input shaft, premium racing frictions and steels, and a shift kit.


Drag racers give serious consideration to performance differences between GM transmissions. Other factors that need to be considered include size, weight, and efficiency. Accordingly, powerglide and a TH400 have a similarity in width whereas their length differs.

Their length may vary between 18 inches on a dragster-style powerglide to 28 inches in a door car. That aside, the TH400 using a standard 4-inch extension housing has a measurement of 29.5 inches. There are times where the transmission measures 34.5 or 38.5 inches.


Servicing your drag transmission can help to prolong its life. This servicing can be carried out every week. It may be useful to drop and inspect the pan after every race weekend on a Monday to ensure unusual debris is taken out of the unit and the unit serviced before the next race day.

On the same note, the powerglide or a TH350 has a filter which is the screen and should be removed and cleaned. You will find a felt or screen element type of filter TH400s and if this is a felt-type filter, it needs to be replaced weekly. There is also a need to replace the pan gasket and torqued to 12-15 lb-ft.


Heat can wear down your transmission especially when the fluid has broken down and viscosity is lost. It is often recommended that you run a temperature gauge to be able to ascertain if the transmission is becoming hot.

If the transmission is around 160 and 180 degrees, you can change the fluid every 40-50 passes. However, if the temperature is ranging around the 200-230 degree mark, it is useful to take proper measures to reduce the operating temperature and fluid changes.

And in cases where the temperature is low, it is useful to use thinner fluids whereas thicker fluids can be used in applications where the temperature surges. Engines with big horsepower engines equipped with automatics often rely on thicker fluids.

Reaction Time

In a bid to win races, you need to make certain modifications to the trans brake. These modifications will offer quick response time and consistent performance. You may be out to get fast-releasing brakes coupled with slower brakes. The slower brakes could help when you need to slow down.

Aside this, you can do certain things internally to the transmission to bring about quicker response time. While using a powerglide, your trans brake can be engaged by holding low gear with the band and Reverse with the band. The reverse clutch area can be used to remove fluid out of the cavity faster to ensure the reverse clutches disengage sooner.

OE Durability

Stock powerglide parts are robust and they are often installed behind six-cylinder engines. There are also powerglide that were installed behind V-8s and these ones featured heavier-duty 1.76:1 ratio planetary set that can support 700-750 hp. There is the 1.82:1 ratio planetary and it is rated at 500-550 hp.

What is more, the factory powerglide, and these ones were the real internal difference. In this case, other internal components are often in the same when it comes to durability and strength. That being the case, the strongest OE-style powerglide is reliable for 750 hp in a 3,000-pound car.

The Bottom Line

The GM transmission recommendations for high performance outlined above will ensure that your ride is better prepared to handle drag racing. It will be rugged, fast, and generally offer impressive performance. If that is what you are out to get, try these recommendations today.

Is My Car Speedometer Accurate?

Is My Car Speedometer Accurate? - Gearstar Performance Transmissions

Have you ever noticed the significant difference between your car speedometer that the speed communicated to you by your GPS or Sat-Nav (satellite navigation)? If you have, do not fret; nothing is wrong with your speedometer, at least not yet. So, is your speedometer accurate? Which is correct: your GPS or your speedometer? In most cases, your speedometer is inaccurate as it reports a much higher speed than your vehicle is traveling at. But then, let us look at how a car speedometer works.

How a Car Speedometer Works

A car speedometer works by measuring the rotations of the wheel, driveshaft, or axle. The speedometer measures how fast those wheels are spinning by using the speed sensor in the transmission. As you well know, speed is defined as the measurement of distance over time. But a speedometer does not measure precisely how fast you travel from one point to another. Your vehicle takes these recorded rotations and applies an excellent arithmetic dose, and the speed is displayed accordingly.

However, the accuracy of a car speedometer depends heavily on the wheels’ wheels or the wheels’ diameter. If you have owned a car for a few years, the speedometer readout will be different now than when you first drove it off the production line or car dealership. But that is if you have not changed the wheel since you purchased the vehicle. This implies that if you change the wheel or tires, the speedometer reading will also vary accordingly. If the new tires come with a larger diameter than the old ones, a faster speed is recorded, and vice versa.

Having under-inflated tires or smaller tires results in a much slower recorded speed. The diameter of the wheels can also change, depending on tire pressure, size, and wear. And these can throw off the accuracy of your speedometer. That is right; a minute change in your car tire’s diameter – by several millimeters – results in incorrect speed recording. This error margin is, however, factored in how vehicle makers calibrate their speedometers.

When you are traveling at 30 mph, the wheels will be rotating at least 6-7 times per second. And this can quickly make a considerable difference of several miles per hour. There is a difference between a speedometer and an odometer. The latter – i.e., odometer – reveals the distance your automobile has traveled while the speedometer shows how fast your car is traveling. Odometer readings are uniquely designed to be accurate, while speedometers are generally calibrated to fudge numbers a little.

Common Car Speedometer Problems

Speedometers can have issues that are generally caused by the numerous components that make up the mechanism. At times, a faulty speedometer head can lead to speedometers not working at all. Another common problem that the speed indicator has is linked to the ‘Check Engine Light.’ When this light turns on, the speedometer stops working. This usually happens when speed sensors no longer send information to the vehicle’s computer. The speed cable may need a replacement when this problem occurs.

Signs and Symptoms of a Bad or Failing Speedometer Sensor

If you are observant, you will notice a few signs which indicate that your speedometer is not working correctly. These include:

    • Check Engine Light going on and off.
    • The speedometer behaving erratically while you are still driving,
    • The speedometer stops working entirely,
    • Overdrive light turning on and off for no apparent reason.

When you notice these signs as displayed on your dashboard, it may be likely that your speedometer has stopped functioning correctly.

Is Your Speedometer Accurate?

Your car speedometer may have an error of plus or minus 4 percent in the United States. This indicates that you could be going faster than what the speedometer reading reveals to you for much lower speeds. But for higher speeds, you could be going 3 miles per hour slower at the minimum. Tires are primarily responsible for this, as under-inflated or over-inflated tires can significantly impact your speedometer’s readout.

The calibration of a speedometer is based on the factory tires of your automobile. After some time, the treads on your vehicle’s factory tires get worn down and will require replacement. Worn tires have been proven to throw off speedometer readouts. Replacing the old tires with new ones that are not remarkably rated for your car can also make your speedometer inaccurate. Here is the big question: how, rigorously, do you test your speedometer’s accuracy?

Testing Speedometer Accuracy

If you have several reasons to suspect that your speedometer is somewhat inaccurate, you can carry out this test while driving, as it is the best way to determine whether your speedometer is accurate or not.

    • Get your hands on a stopwatch.
    • As soon as you pass a mile marker on the highway, start the stopwatch.
    • Then, stop the watch when you pass the next mile marker.
    • You can take the second hand of the stopwatch as your speed. It would be an excellent idea to bring a friend along for the ride to avoid distractions.

A blown a fuse or damaged wiring is more than enough to throw your speedometer out of whack. A malfunctioning engine control unit or sensor could report erroneous speed. To take care of this, have an auto shop or technician look at your vehicle. If there is an issue with your speedometer, the mechanic will fix it for you ASAP.

The Bottom Line

So, is your speedometer accurate? Well, you have read all the reasons why your speedometer could be accurate or inaccurate. This is not to imply that you should not trust your speedometer. It only means that you need to be careful anytime you are driving on the highway. The type of tires you use could also impact the accuracy of your speedometer. Make sure you go for factor or model-specified tires for your vehicle. This ensures that your speedometer will give more accurate readouts than when you use unrated automobile tires.

Can Low Transmission Fluid Reduce Engine Power?

Can Low Transmission Fluid Reduce Engine Power? - Gearstar Performance Transmissions

From getting to work to getting the kids to school to getting to your best friend’s house, you depend on your vehicle in a vast number of ways. To have a smooth run of your vehicle, all the entire architecture and engine mechanism must perform optimally. To start with, the engine – which is the heart and also a delicate part of the vehicle, must be in a healthy state all times.

How do you feel when you have your foot on the accelerator and you there is a drag in the movement of the vehicle? Frustrating. Transmission could be responsible. In days-gone-by of ancient vehicles, mere changing of the spark plugs, plug wires or even the carburetor would bring about a drastic change in the ‘drag’ movement. In modern vehicles where sensors are embedded, there are all kinds of culprits behind your car reluctance to accelerate.

You could be confused how transmission and/ transmission fluid is very important to vehicle’s engines. Here is why. But before getting to know the importance of a transmission fluid, this is what transmission means. Transmission refers to a gearbox that makes use of gear and gear trains to provide speed and torque conversions from a rotating power source, the engine, to another device – wheels.

Transmission fluid, on the other hand, is used to lubricate the components of a car’s transmission for optimum performance. If you have a faulty transmission, it will affect the smooth run of your engine which in turn makes you frustrated. In a situation where there is leakage or low transmission fluid, the engine would not provide maximum speed your vehicle.

What Is Engine Power?

To fully understand how engine works, knowing the power your engine can produce is important. Engine power is the amount of twisting force available at the crankshaft in the engine. The more torque you have, the more pulling power the engine has; hence, the force you feel when accelerating your vehicle.

The torque measurement provides an indication of how fast the engine will be able to move your vehicle’s weight. When driving and you have “engine power induced” light on, most times, it is the transmission losing its fluid. Also, the “check engine” light may pop on. Do not panic yet. Remain calm when driving your vehicle.

Ideally, when these lights come on, they mean your vehicle’s performance has been reduced to avoid damaging and wearing off the engine. And most modern cars are with series of sensors, which makes the electronic control unit to trigger the Reduced Power Mode after it has detected a system failure in the engine.

What Triggers the “Reduced Engine Power” Warning Light?

There are lots of reasons why your reduced engine light is on and you may be confused on how to make it go off. However, one of the most common causes of this problem is a fault with your electronic throttle actuator system. Modern cars utilize this in the stead of a tradition mechanical throttle body. In a throttle actuator control system, the Engine Control Unit masterminds two accelerator position sensors to determine your desire to accelerate. The device calculates the appropriate throttle response from two throttle position sensors.

Once it has the necessary information from the sensors, the Engine Control Unit uses an actuator motor to maneuver the throttle, thus controlling airflow into your vehicle’s engine. Any problem with your throttle actuator control system can easily trigger the “reduced engine power” warning light on the dashboard of your vehicle. For quick instance, the problem could be one of the vehicle’s sensors, the throttle body or even the accelerator pedal assembly.

Solutions to Reduced Engine Power Light

When you start your vehicle and you notice the Reduced Engine Power light is on, it is very much advisable not to drive. And if you are already at top speed on the highway, it is expected of you to visit a technician immediately. When you notice the light is off, the next thing is for you to scan your vehicle.

Sometimes, error codes and faults that occur are stored within the systems of your vehicle even if the scan occurs after the light goes off. In days-gone-by, older vehicles do not have computer systems which makes detecting fault more difficult. And finding these faults could be very expensive as well.

How do you fix this problem; reduced engine power light? Before driving to the mechanic or a technician, you could handle this yourself. If you drive a reduced engine power car, it could cause more problems before you get to the mechanic that will have your vehicle fixed. Here are the simple steps you can take:

1. Replace the Air Flow Sensor

There are couple of ways to detect if your vehicle’s air sensor is not working properly. When you start the engine, open the hood or bonnet. Try to locate the air flow sensor and tap severally. If the engine falters slightly, the air flow is dirty. Alternatively, stop the engine and disconnect the sensor.

Start the engine afterwards. The engine will sense the removal of the air flow sensor and will go into a back-up running mode. This is a simple fault with a pretty simple fix. Replacing the air flow sensor is the best alternate when you discover it is dirty and enjoy a return to your standard engine power!

2. Replace Air Filter

Another step in having a healthier engine is to make sure you have a clean air filter in perfect working condition. In almost all modern cars, the air filter is located in a rectangular box. It is placed to one side of the engine block just near the fender. Remove the filter itself and have a check under a light.

If no light or very little light comes through, that means the air filter is clogged and must be replaced immediately. When engine response to distorted conditions begins, transmission fluid is one of the major things to replace immediately. Hence, the reduction in engine power which would make the engine wear and tear in no time.

Five Things To Never Do To Your Ford’s Automatic Transmission

Automatic transmissions in Ford are pretty much standard nowadays — if you want a manual, you may have to request for it or get it custom built. Automatic has made driving seamless and easier than ever, and not to forget the added power output, which manual models can’t deliver. But just because it has revolutionized the way we drive, doesn’t mean it will work as smoothly as new for years to come. You will need to do a lot of things to keep it in tip-top shape. But you will also need to avoid a few things to prevent its breakdown.

Here are a few things you should never do to Ford’s automatic transmission:

Don’t drive through deep water

It’s tempting to test your new Ford truck’s ability to cross a creek. Or perhaps, the roads are flooded, and you have no way around to get home. But if you drive through deep water, the chances of transmission damage quadruple. Water can go into the vents of your Ford’s auto transmission and may destroy the transmission beyond repair. Sure, you may get lucky, but it’s usually not worth the risk, as transmission repairs are heavy on pockets.

Avoiding going straight from reverse to drive when the vehicle is mobile

Many drivers whip the transmission into drive while they are backing up, thinking it’s fine to do it. But you might want to change this habit or avoid it in the first place. When you switch from reverse to drive or vice versa without stopping the vehicle completely, you put pressure on the transmission bands and clutch plates, which can ruin the transmission and lead to hefty repairs. It’s best to stop the vehicle first and then switch to reverse from the drive and vice versa.

Avoid leaving the transmission in the drive when idling

Whether you stopped your Ford because of traffic or any other reason, leaving the transmission in drive can lead to overheating inside it, which can impact its lifespan. So, when you are idling the vehicle for a while, make sure to shut the transmission down completely. This way, Ford’s auto transmission won’t be sending power, which prevents overheating.

Don’t forget to change the transmission fluid

Many people overlook the importance of replacing automatic transmission fluid (ATF) under normal driving conditions. However, it’s a blunder that invites plenty of transmission issues, including its complete failure. As a rule of thumb, it’s best to avoid driving with dirty transmission fluid. Always replace it as per the manufacturer’s recommendations.

Don’t coast down in neutral

Many drivers think of saving gas when coming downhill by coasting down in neutral. However, that’s not true. While it may work with manual transmissions, Ford’s auto transmission may deliver more gas to the engine to prepare for the start because of the increase in the ROM while in neutral. So, you are not saving gas but using more by coming downhill in neutral.

It’s also vital to avoid driving your Ford when you are noticing transmission fluid leaks. In such cases, the best course of action is to visit a repair shop immediately and get the leaks fixed.

If you are looking for automatic transmission for your Ford, get in touch with us and discuss your requirements. We are a team of experts who custom build Ford’s auto transmission to improve your driving experience.